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Two-post-Newtonian approximation of the scalar-tensor theory with an intermediate-range force for general matter

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Science China(Physics,Mechanics & Astronomy) 2015年第3期58卷 8-15页

作者： deng xuemei Purple Mountain Observatory Chinese Academy of Sciences

Some future space missions measure distances of laser links and angles with unprecedented precision, allowing us to test theories of gravity up to the two-post-Newtonian （2PN） order. Besides, investigation of an intermediate-range force has been of considerable interests in gravitational experiments. Inspired by these ideas, within the framework of the scalar-tensor theory with an intermediate- range force, its 2PN approximation is obtained with Chandrasekhar＇s approach. It includes the 2PN metric and equations of motion for general matter without specific equation of state. The conserved quantities to the 2PN order are isolated with the aid of the energy-momentum complex. We also discuss the prospect of testing and distinguishing the intermediate-range force with the orbital motions of celestial bodies and spaeecrafts.

关键词： gravitation intermediate-range force post-Newtonian approximation

Constraints on a scalar-tensor theory with an intermediate-range force by binary pulsars

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Science China(Physics,Mechanics & Astronomy) 2011年第11期54卷 2071-2077页

作者： deng xuemei Purple Mountain Observatory Chinese Academy of Sciences Nanjing 210008 China

Searching for an intermediate-range force has been considerable interests in gravity experiments. In this paper, aiming at a scalartensor theory with an intermediate-range force, we have derived the metric and equations of motion （EOMs） in the first post- Newtonian （1PN） approximation for general matter without specific equation of state and N point masses firstly. Subsequently, the secular periastron precession ω of binary pulsars in harmonic coordinates is given. After that, ω of four binary pulsars data （PSR B1913＋16, PSR B1534＋12, PSR J0737-3039 and PSR B2127＋11C） have been used to constrain the intermediate-range force, namely, the parameters G and λ. α and λ respectively represent the strength of the intermediate-range force coupling and its length scale. The limits from four binary pulsars data are respectively A = （4.95 ±0.02）× 10^8 m and a = （2.30±0.01）× 10^8 if β = 1, where fl is a parameter like standard parametrized post-Newtonian parameter βPPN. When three degrees of freedom （α, λ and β = β - 1 ） in lσ confidence level are considered, it yields α = （4.21 ±0.01）× 10^4, λ= （4.51 ±0.01）× 10^7 m and β = （-3.30 ±0.01）× 10^-3. Through our research on the scalar-tensor theory with the intermediate-range force, it shows that the parameter α is directly related to the parameter γ （α = （1 - γ）/（1 ＋ γ））. Thus, this presents the constraints on 1 - γ by binary pulsars which is about 10^-4 for three degrees of freedom.

关键词： binary pulsars intermediate-range force post-Newtonian approximation

Global Solutions of Shock Reflection by Wedges for the Nonlinear Wave Equation

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Chinese Annals of Mathematics,Series B 2011年第5期32卷 643-668页

作者： xuemei deng Wei XIANG School of Mathematical Sciences Xiamen University Xiamen 361005 Fujian China Corresponding author. School of Mathematical Sciences Fudan University Shanghai 200433 China

When a plane shock hits a wedge head on, it experiences a reflection-diffraction process and then a self-similar reflected shock moves outward as the original shock moves forward in time. In this paper, shock reflection by large-angle wedges for compressible flow modeled by the nonlinear wave equation is studied and a global theory of existence, stability and regularity is established. Moreover, C^0,1 is the optimal regularity for the solutions across the degenerate sonic boundary.

关键词： Compressible flow Conservation laws Nonlinear wave system Regularreflection

Global classical solution to the three-dimensional isentropic compressible Navier-Stokes equations with general initial data

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Science China Mathematics 2012年第12期55卷 2457-2468页

作者： deng xuemei ZHANG PeiXin ZHAO JunNing School of Mathematical Sciences Xiamen University Xiamen 361005 China College of Science China Three Gorges University Yichang 443002 China School of Mathematical Sciences Huaqiao University Quanzhou 362021 China

We establish the global existence and uniqueness of classical solutions to the Cauchy problem for the isentropic compressible Navier-Stokes equations in the three space dimensions with general initial data which could... 详细信息

关键词： compressible Navier-Stokes equations large viscosity coefficient global classical solutions

Construction of a dual fluorescence whole-cell biosensor to detect N-acyl homoserine lactones

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Journal of Environmental Sciences 2014年第2期26卷 415-422页

作者： xuemei deng Guoqiang Zhuang Anzhou Ma Qing Yu Xuliang Zhuang Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Detection of N-acyl homoserine lactones （AHLs） is useful for understanding quorum sensing （QS） behaviors, including biofilm formation, virulence and metabolism. For detecting AHLs and indicating the host cells in situ, we constructed the plasmid pUCGMA2T1-4 to make a dual fluorescent whole- cell biosensor based on the AhlI/R AHL system of Pseudomonas syringae pv. syringae B728a. The plasmid contains three components： constitutively expressed enptll：：gfP for indicating host cells, Pahll：：mcherry that produces red fluorescence in response to AHL, and the ahIR gene that encodes an AHL regulatory protein. Meanwhile, two copies of T1-4 （four tandem copies of a transcriptional terminator） were added into the plasmid to reduce background. The results showed that when the plasmid was placed into Escherichia coli, the dual fluorescence whole-cell biosensor was able to respond with red fluorescence within 6 hr to 5 × 10^-8-1 × 10^-5 mol/L of 3OC6-HSL. Bright green fluorescence indicated the host cells. Furthermore, when the plasmid was transferred to wild- type Pseudomonas PhTA125 （an AHL-producing bacterium）, it also showed both green and red fluorescence. This result demonstrates that this plasmid can be used to construct whole-cell indicators that can indicate the AHL response and spatial behaviors of microbes in a mi tal niche

关键词： whole-cell biosensor quorum sensing dual fluorescence gfp mcherry indicator

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油茶‘湘林210’抗干旱特性研究

中南林业科技大学学报 2024年第1期44卷 37-48页

作者：王志超何之龙陈永忠邓雪梅王瑞赖杭桂海南大学热带农林学院海南海口570100 湖南省林业科学院国家油茶工程技术研究中心湖南长沙410004

【目的】研究当前油茶主推品种‘湘林210’苗木在干旱胁迫下光合特性及相关生理指标的变化规律,为后续油茶抗旱育种和抗旱基因机理研究提供理论支持。【方法】以‘湘林210’5年生油茶苗为试验材料,以当地区域良种‘衡东2号’同龄苗木为... 详细信息

【目的】研究当前油茶主推品种‘湘林210’苗木在干旱胁迫下光合特性及相关生理指标的变化规律,为后续油茶抗旱育种和抗旱基因机理研究提供理论支持。【方法】以‘湘林210’5年生油茶苗为试验材料,以当地区域良种‘衡东2号’同龄苗木为对照,采用盆栽控水模拟干旱胁迫试验,设置正常供水对照组(CK,土壤最大持水量的75%~85%),干旱梯度设置轻度干旱(T1,土壤最大持水量的55%~60%)、中度干旱(T2,土壤最大持水量的40%~45%)和重度干旱(T3,土壤最大持水量的30%~35%)。每梯度进行光合荧光参数测定并采集叶片进行理化指标检测。【结果】1)随着干旱程度的加深,油茶苗木各项指标变化差异显著,光合参数中最小初始荧光(Fo)为显著性上升趋势,净光合速率(P_(n))、气孔导度(G_(s))、胞间CO_(2)浓度(C_(i))、蒸腾速率(T_(r))、最大光化学效率(F_(v)/F_(m))均呈显著下降趋势,部分表现极显著,且下降幅度随干旱程度的加深差异越显著。2)随着干旱程度的加深,叶片中还原性谷胱甘肽(GSH)含量、丙二醛(MDA)含量、脯氨酸(Pro)含量、苯丙氨酸解氨酶(PAL)活性均呈显著上升趋势,超氧化物歧化酶(SOD)活性呈先上升后降低的变化趋势,但整体呈上升趋势。3)对10个指标进行相关性、主成分和隶属函数分析,得出油茶抗旱性与10个指标存在显著相关,部分极显著相关。【结论】油茶具有一定的抗干旱性,在受干旱胁迫时品种之间的抗旱能力强度存在差异,‘湘林210’抗旱性能强于‘衡东2号’,因此在持续干旱条件下‘湘林210’存活力更强。

关键词：油茶干旱胁迫光合荧光特性生理指标

基于聚类分析和判别分析的蛋壳颜色分级方法研究

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中国家禽 2024年第3期46卷 1-6页

作者：何爽贺旗郑中华龙君江徐建生邓学梅中国农业大学动物科学技术学院动物遗传资源与分子育种实验室北京100193 山东龙盛农牧集团有限公司山东临沂276000 江西东华种畜禽有限公司江西抚州330029

为制定客观、准确的蛋壳颜色分级体系,研究在用Lab体系量化蛋壳颜色的基础上提出了一种蛋壳颜色分级标准的建立方法,先确定合适的聚类簇个数k,通过K-均值聚类分析处理训练样本,再通过贝叶斯判别分析检验聚类效果并获得各等级判别式,最... 详细信息

为制定客观、准确的蛋壳颜色分级体系,研究在用Lab体系量化蛋壳颜色的基础上提出了一种蛋壳颜色分级标准的建立方法,先确定合适的聚类簇个数k,通过K-均值聚类分析处理训练样本,再通过贝叶斯判别分析检验聚类效果并获得各等级判别式,最后据此对测试样本进行分类,计算色差以检验分类效果。结果显示:训练样本的分类准确率达95.0%,测试样本各类别间颜色差异大,类别内颜色一致性较高,表明其分类效果良好。依据该方法可以针对特定群体构建专用分级标准,实现蛋壳颜色的合理分级与精准判定,进而为蛋壳颜色整齐度的提高提供指导。

关键词：蛋壳颜色分级聚类分析判别分析色差仪

Molecular cloning and characterization of the endothelin 3 gene in black bone sheep

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Journal of Animal Science and Biotechnology 2018年第4期9卷 847-857页

作者： Hesham Y.A.Darwish Yuanyuan Zhang Kai Cui Zu Yang Deping Han Xianggui Dong Huaming Mao Weidong deng xuemei deng National Engineering Laboratory for Animal Breeding and Key Laboratory of Animal Genetics Breeding and Reproduction of the Ministry of AgricultureChina Agricultural University Animal Production Research Institute Agricultural Research Center Ministry of Agriculture and Land Reclamation College of Veterinary Medicine China Agricultural University College of Animal Science and Technology Yunnan Agricultural University

Background: Black bone sheep was first discovered in Yunnan province of China in 1970, with unique black pigmentation on the body and internal organs. Endothelin 3(EDN3) has been known as a key gene causing hyperpigmentation in black bone chicken, the Silky ***: In this study, EDN3 was employed as a candidate gene for regulating black color pigmentation. First,EDN3 was cloned from sheep to obtain the full-length cDNA by using the rapid amplification of cDNA ends(RACE).Genomic EDN3 was screened and a total of thirty predicted single nucleotide polymorphisms(SNPs) were genotyped for allele and genotype frequency analysis in a case-control study involving two black bone sheep populations. Genomic copy number analysis of EDN3 in sheep was conducted to measure the variation in copy number. EDN3 expression levels were observed among the groups in adult liver, lymph node, and kidney tissues, as well as embryo kidney samples. Also, among the tissues of black bone and non-black bone ***: The size of the full-length cDNA was 1,578 bp, which included 426 bp of 5′-untranslated region(5′-UTR),an open reading frame(ORF) of 639 bp encoding a protein of 212 amino acids, and a 3′-UTR of 513 bp. Genotype and allele frequencies of all the discovered SNPs were found insignificantly different in black bone and non-black bone sheep(P > 0.05). Genomic copy number analysis of EDN3 in sheep revealed no significant difference between the two sheep groups. No significant variations were found in the adult liver and kidney embryo samples. However,the expression in lymph node and kidney tissue was significantly higher in black bone sheep than that in non-black bone sheep(P < 0.05). Significant variations in the EDN3 expression levels were observed among the tissues of nonblack bone ***: The findings of the present study indicate that unlike in Silky chickens, EDN3 is not responsible for hyperpigmentation but may play a key functional role in immune and excretory

关键词： Black pigmentation Expression level Sequence analysis SNP

Integrating host biological and ecological variables to predict probability of haemosporidian infection in raptors

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Avian Research 2024年第2期15卷 255-264页

作者： Kai Gao xuemei Yang Xi Huang Wenhong deng Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering College of Life SciencesBeijing Normal UniversityBeijing100875China

Variations in host traits that influence their exposure and susceptibility may impact probability of vector-transmitted ***,identifying the predictors of infection probability is necessary to understand the risk of disease outbreaks during expanding environmental ***,we conducted a large survey based on microscopic examination and molecular analysis of haemosporidian parasite infection in raptors rescued at the Beijing Raptor Rescue *** these data with biological and ecological variables of the raptors,we determined predictors that affect the probability of haemosporidian infection using generalized linear mixed models and multimodel *** results showed that infection probability exhibited considerable variation across host species in raptors,and body mass,sex,and evolutionary history played relatively weaker roles in driving infection ***,activity pattern,age,geographic range size,migration distance,and nest type were important predictors of the probability of haemosporidian infection,and the role of each predictor differed in the three main haemosporidian genera(Plasmodium,Haemoproteus,and Leucocytozoon).This macro-ecological analysis will add to our understanding of host traits that influence the probability of avian haemosporidian infection and will help inform risk of emerging diseases.

关键词： Activity pattern Emerging infectious diseases Infection probability Interspecific variation Migratory exposure